After the stunned silence brought on by Ariel Sharon's health crisis, Israeli political circles are discussing in earnest how to fill the colossal hole left by his removal from the scene.

The weekend's political radio talk shows sprang back to life with analysis of what could be a major turning point not just for Israel, but for the whole region and the world.

The main subject is the fate of Kadima, the party founded by Mr Sharon late last year, which had seemed to be cruising towards almost certain victory in the general election on 28 March.

The party is made up of prominent defectors from both sides of Israel's traditional left-right divide, forming a new centrist movement that could win wide electoral support.

The key question is: Without the glue provided by Mr Sharon's leadership, will the Kadima members - they don't even have a collective name yet - stick together to see through his vision, or fall apart squabbling?

Veteran adversaries

At the moment, Kadima is led by acting Prime Minister Ehud Olmert, considered a capable and seasoned politician, but with none of Mr Sharon's charisma or the heroic status he has secured among Israelis.

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Mr Olmert has been holding talks with veteran ex-Prime Minister Shimon Peres that are believed to be designed to keep Mr Peres on board, amid reports that the Labour party is desperate to tempt him back.

Mr Peres, 81, left Labour after seven decades with the party when it rejected his bid to return to the leadership last November.

With the tectonic plates of Israeli politics visibly shifting, Mr Peres came to Kadima at the invitation of Mr Sharon, a lifelong friend but political adversary.

He was offered any position in Kadima he wanted short of party leader - an obvious choice being the foreign ministry, although jobs have not been allocated yet.

With Mr Sharon's presumed political demise and Mr Olmert's elevation, the latter may also be able to offer the ever-ambitious Mr Peres the bonus role of deputy prime minister as well.

It was not until Sunday that Mr Peres publicly offered support for Mr Olmert as acting party head, a delay which angered some Kadima members, who accused him of following his own interests.

Outmanoeuvred

The right-wing Likud party, co-founded by Mr Sharon after he left the army in 1973, was dealt a severe blow when he abandoned it - having already split the party with last year's withdrawal of troops and settlers from the Gaza Strip.

Binyamin Netanyahu won back the leadership, and - after being repeatedly outmanoeuvred by Mr Sharon - is considered to have greatly improved chances against Mr Olmert.

I want everyone to return to the Likud so that we can continue running the nation

Likud official Uzi Cohen

Likud also lost some big-name defectors, but most observers believe the wounds are much too raw for any of them, however right-wing, to return, even if the Kadima project collapses.

Likud officials quoted in Sunday's press said that once Mr Sharon's fate was clear, the party would invite former members to "come home".

"I want everyone to return to the Likud so that we can continue running the nation," said prominent party official Uzi Cohen.

He said it was not a time for settling scores but "a time to give leadership to the people of Israel".

Unless there is a big turnaround - which cannot be ruled out, although Likud lies third behind Labour in polls - the party's future therefore probably lies in alliance with the far-right and religious parties, who fell out with Mr Sharon over the Gaza plan.

But many commentators say the formerly uncrossable, strongly ideological, pro-settler constituency represents just what most Israeli voters want to get away from.

The new politics is characterised by the muscular pragmatism practised by Mr Sharon.

Trumped

Labour is under new leadership of former union boss Amir Peretz, which makes it hard to predict the party's future prospects.

Labour's long-standing platform, separation between Israel and the Palestinians, has been trumped by Mr Sharon's presumed vision - although he never spelt it out explicitly - of drawing Israel's borders to the country's advantage unilaterally, without negotiations.

That seems to be the view of a large proportion of the electorate, according to the latest polls which suggest Kadima will still get 36-42 seats in the 120-seat Knesset, even without Mr Sharon.

That would enable it to head a coalition made up perhaps of other secular centre and centre-left groups like Shinnui, Labour and Arab parties.

Commentators say that, even in the notoriously fractious world of Israel politics, the nascent Kadima party does not have time to tear itself apart in the 80-odd days left before the election.

It is unclear if Washington will pin its hopes on a Sharon-less Kadima as it did when Mr Sharon - a key US ally - was still at its centre.

So far the Americans have remained silent on the topic, although US backing for the upholding of Mr Sharon's legacy would be a powerful endorsement.